This paper proposes the virtual flux based direct power control for Vienna rectifier. No need for the input voltage sensors, the current regulation loop and PWM voltage modulation block along with the active and reactive power decoupling are some of the salient advantages of this method that make it suitable for controlling the conventional active rectifiers. However, due to the three-level nat...

GeV beams of light ions and electrons are used for creating a high flux of real and virtual photons, with which some problems in Nuclear Astrophysics are studied. GeV B beams are used to study the Coulomb dissociation of B and thus the Be(p, γ)B reaction. This reaction is one of the major source of uncertainties in estimating the B solar neutrino flux and a critical input for calculating the B ...

This and the accompanying paper present an overview of the face and body animation object in the MPEG-4 Version 2 standard. The MPEG-4 standard includes the representation, compression of virtual human models and their interface with other MPEG-4 objects, with bit rate requirements as low as 1 Kbit/second. In this paper, we give an overview of animation techniques for the FBA object, and in the...

This and the accompanying paper present an overview of the face and body animation object in the MPEG-4 Version 2 standard. The MPEG-4 standard includes the representation, compression of virtual human models and their interface with other MPEG-4 objects, with bitrate requirements as low as 1 Kbit/second. In this paper we give an overview of geometrical modeling techniques for the FBA object, a...

Aims. We study the visibility of sunspots and its influence on observed values of sunspot region parameters. Methods. We use Virtual Observatory tools provided by AstroGrid to analyse a sample of 6862 sunspot regions. By studying the distributions of locations where sunspots were first and last observed on the solar disk, we derive the visibility function of sunspots, the rate of magnetic flux ...

active filters have proven to be more effective than passive techniques to improve power quality and to solve harmonic and power factor problems due to nonlinear loads. this paper proposes a control scheme based on the instantaneous active and reactive power. the inverter of this active filter is a three-phase, two-level converter. space vector technique is used as modulators and pattern genera...

iran’s industry has had a considerable number of difficulties to perform so well as was expected in the post – revolutionary era. unfavorable legal, political environments combined with eight –year imposed war may be singled out as the root causes of such performances. however, this paper argues that our industry’s lack of realization of its dire need to adapt to the emerging unprecedented envi...

<p style='text-indent:20px;'>In this paper, we introduce a simple local flux recovery for <inline-formula><tex-math id="M1">$ \mathcal{Q}_k $</tex-math></inline-formula> finite element of scalar coefficient diffusion equation on quadtree meshes, with no restriction the irregularities hanging nodes. The construction requires specific ad hoc tweaking nodes id="M2"&gt...